U.S. patent application number 10/878547 was filed with the patent office on 2005-05-05 for solid immersion lens moving device and microscope using the same.
This patent application is currently assigned to HAMAMATSU PHOTONICS K.K.. Invention is credited to Arata, Ikuo, Tanabe, Hiroshi.
Application Number | 20050094258 10/878547 |
Document ID | / |
Family ID | 34544049 |
Filed Date | 2005-05-05 |
United States Patent
Application |
20050094258 |
Kind Code |
A1 |
Tanabe, Hiroshi ; et
al. |
May 5, 2005 |
Solid immersion lens moving device and microscope using the
same
Abstract
A solid immersion lens moving device is provided with a first
arm member 71, to which is connected a solid immersion lens holder
5 that supports a solid immersion lens 3; a first arm member
rotation source 72, which rotates this first arm member 71 within
an X-Y plane that is substantially parallel to an observed object;
a second arm member 73, holding this first arm member rotation
source 72; and a second arm member rotation source 74, having a
rotation axis at a position that is non-coaxial to the rotation
axis of first arm member rotation source 72 and rotating second arm
member 73 within the X-Y plane. By enabling the movement of solid
immersion lens 3 to a desired position within the X-Y plane by the
rotation of the two arm members 71 and 73, the need to make the
component parts long in the orthogonal X and Y directions is
eliminated and a simple arrangement that occupies a small area is
provided. A solid immersion lens moving device, with which low cost
is realized while realizing compactness of the device, and a
microscope equipped with the same are thereby realized.
Inventors: |
Tanabe, Hiroshi;
(Hamamatsu-shi, JP) ; Arata, Ikuo; (Hamamatsu-shi,
JP) |
Correspondence
Address: |
MORGAN LEWIS & BOCKIUS LLP
1111 PENNSYLVANIA AVENUE NW
WASHINGTON
DC
20004
US
|
Assignee: |
HAMAMATSU PHOTONICS K.K.
|
Family ID: |
34544049 |
Appl. No.: |
10/878547 |
Filed: |
June 29, 2004 |
Current U.S.
Class: |
359/368 ;
359/391 |
Current CPC
Class: |
G01N 21/8806 20130101;
G01N 21/956 20130101; G02B 21/26 20130101; G02B 21/33 20130101 |
Class at
Publication: |
359/368 ;
359/391 |
International
Class: |
G02B 021/00; G02B
021/26 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 31, 2003 |
JP |
P2003-372777 |
Claims
What is claimed is:
1. A solid immersion lens moving device, moving a solid immersion
lens within an X-Y plane that is substantially parallel to an
observed object, comprising: a first arm member, being connected to
a solid immersion lens holder that supports said solid immersion
lens; a first arm member rotation source, rotating said first arm
member within said X-Y plane; a second arm member, holding said
first arm member rotation source; and a second arm member rotation
source, having a rotation axis at a position that is non-coaxial to
the rotation axis of said first arm member rotation source and
rotating said second arm member within said X-Y plane.
2. The solid immersion lens moving device according to claim 1,
further comprising a Z-direction movement source for moving said
second arm member rotation source in a Z-direction that is
orthogonal to said X-Y plane.
3. The solid immersion lens moving device according to claim 1,
further comprising an optical coupling material supplying means,
supplying an optical coupling material for optically coupling said
solid immersion lens to said observed object.
4. The solid immersion lens moving device according to claim 3,
further comprising a drying gas supplying means, supplying a gas
for drying said optical coupling material.
5. The solid immersion lens moving device according to claim 1,
wherein said solid immersion lens holder is equipped with an
outwardly extending arm part, said arm part being detachably
connected to the first arm member.
6. The solid immersion lens moving device according to claim 1,
wherein said first arm member is detachably connected to said first
arm member rotation source.
7. The solid immersion lens moving device according to claim 1,
wherein said second arm member is arranged to have a curved
form.
8. The solid immersion lens moving device according to claim 1,
wherein said solid immersion lens holder is formed to have a
cylindrical form, with which the inner diameter is large in
comparison to the outer diameter of the solid immersion lens, and
said solid immersion lens is positioned within the inner periphery
of said solid immersion lens holder with the bottom surface of said
solid immersion lens protruding from an opening in the bottom
surface of said solid immersion lens holder.
9. A solid immersion lens moving device comprising: a microscope,
for observing said observed object through said solid immersion
lens, wherein the solid immersion lens moving device according to
claim 1 is detachably mounted to said microscope.
10. A microscope, for performing observation of a sample in order
to obtain internal information on the sample, comprising: an
optical system, including an objective lens, onto which light from
said sample is made incident, and guiding an image of said sample;
and the solid immersion lens moving device according to claim 1;
wherein said solid immersion lens moving device moves said solid
immersion lens between an inserted position, which contains an
optical axis from said sample to said objective lens; and a standby
position, which is located away from said optical axis.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to a solid immersion lens moving
device for moving a solid immersion lens and also relates to a
microscope using this solid immersion lens moving device.
[0003] 2. Related Background of the Invention
[0004] A solid immersion lens (SIL) is known as a lens for
magnifying an image of an observed object. This solid immersion
lens has a hemispherical shape or a hyperhemispherical shape,
called a Weierstrass sphere, and is a microlens with a size of
approximately 1 mm to 5 mm. When this solid immersion lens is used,
since both the numerical aperture NA and the magnification are
increased, observation at high spatial resolution is enabled.
[0005] As a solid immersion lens moving device for moving a solid
immersion lens to an observation position of an observed object in
order to carry out observation using this solid immersion lens,
there is known a device, which performs X-Y movements of a holding
box, holding a solid immersion lens, by means of X-Y actuators
(see, for example, Document 1: U.S. 2003/0098692A1). There is also
known a device, which performs X-Y-Z movements of a cantilever,
holding a solid immersion lens, by means of piezo elements (see,
for example, Document 2: Japanese Patent Application Laid-Open No.
2001-189359).
SUMMARY OF THE INVENTION
[0006] However, with the former art wherein X-Y movements of a
holding box are carried out by means of X-Y actuator, as is
generally pointed out with X-Y actuators, component parts are
required to be made long in the orthogonal X and Y directions and
since the occupied area thus becomes large, compactness cannot be
achieved. With the latter art wherein X-Y-Z movements of a
cantilever are carried out by means of piezo elements, since large
strokes cannot be achieved, an X-Y-Z stage is provided separately
at the observed object side, and thus the cost is high.
[0007] This invention has been made to resolve such problems, and
an object thereof is to provide a solid immersion lens moving
device, with which compactness can be realized while realizing low
cost, and a microscope equipped with the same.
[0008] This invention provides in a solid immersion lens moving
device, which moves a solid immersion lens within an X-Y plane that
is substantially parallel to an observed object, a solid immersion
lens moving device comprising: a first arm member, being connected
to a solid immersion lens holder that supports the solid immersion
lens; a first arm member rotation source, rotating this first arm
member within the X-Y plane; a second arm member, holding this
first arm member rotation source; and a second arm member rotation
source, having a rotation axis at a position that is non-coaxial to
the rotation axis of the first arm member rotation source and
rotating the second arm member within the X-Y plane.
[0009] With such a solid immersion lens moving device, the second
arm member and the first arm member rotation source, which is held
by the second arm member, are rotated within the X-Y plane that is
substantially parallel to the observed object by the second arm
member rotation source. Also, by the first arm member rotation
source, the rotation axis of which is positioned non-coaxially to
the rotation axis of the second arm member rotation source, the
first arm member, to which is connected the solid immersion lens
holder that supports the solid immersion lens, is rotated within
the X-Y plane. Since the solid immersion lens is thus moved to a
desired position within the X-Y plane by the rotation of two arm
members, there is no need to make the component parts long in the
orthogonal X and Y directions and a simple arrangement that
occupies a small area is provided.
[0010] Here, a Z-direction movement source, for moving the second
arm member rotation source in a Z-direction that is orthogonal to
the X-Y plane, is preferably equipped. In this case, the solid
immersion lens can be moved freely to a desired position in
three-dimensional directions by the solid immersion lens moving
device.
[0011] Also, an optical coupling material supplying means, for
supplying an optical coupling material for optically coupling the
solid immersion lens to the observed object, is preferably
equipped. In this case, light flux of high numerical aperture (NA)
can be transmitted. The inherent resolution of the solid immersion
lens can thereby be exhibited.
[0012] Also, a drying gas supplying means, for supplying a gas for
drying the optical coupling material, is preferably equipped. In
this case, the drying of the optical coupling material is promoted,
thereby enabling observation to be carried out immediately.
[0013] The solid immersion lens holder may also be equipped with an
arm part, which extends outwards, and this arm part may be arranged
to be detachably connected to the first arm member. In this case,
exchange of the lens together with the arm part is enabled for lens
exchange and lens exchange is thus facilitated since there is no
need to handle a minute solid immersion lens. An arrangement is
also possible wherein the first arm member is detachably connected
to the first arm member rotation source.
[0014] Also, the second arm member is preferably arranged to have a
curved form. In this case, the second arm member can be kept away
readily from the field of view of the observed object.
[0015] Also, the solid immersion lens holder may be arranged to
have a cylindrical form, with which the inner diameter is large in
comparison to the outer diameter of the solid immersion lens, and
be arranged so that the solid immersion lens is positioned within
the inner periphery of the solid immersion lens holder with the
bottom surface of the solid immersion lens protruding from an
opening in the bottom surface of the solid immersion lens holder.
In this case, the solid immersion lens is moved to a desired
observation position by being moved in a sliding manner across the
observed object while being hitched onto the inner peripheral
surface of the solid immersion lens holder that moves within the
X-Y plane. By then moving the solid immersion lens holder or the
observed object in the Z-direction and then further moving the
solid immersion lens holder within the X-Y plane and thus away from
the solid immersion lens, observation can be carried out with all
component parts being moved away from the field of view of the
observed object.
[0016] Also, a microscope, for observing the observed object
through the solid immersion lens, is preferably equipped and the
above-described solid-immersion lens moving device is preferably
mounted detachably to this microscope. This arrangement is
convenient for performing observation upon removing the solid
immersion lens moving device, for performing observation upon
mounting another lens moving device, etc.
[0017] Also, this invention provides in a microscope, which is
equipped with a solid immersion lens moving device and is for
performing observation of a sample in order to obtain internal
information on the sample, a microscope comprising: an optical
system, including an objective lens, onto which light from a sample
that is to be an observed object is made incident, and guiding an
image of the sample; and the above-described solid immersion lens
moving device; and characterized in that the solid immersion lens
moving device moves the solid immersion lens between an inserted
position, which contains an optical axis from the sample to the
objective lens; and a standby position, which is located away from
the optical axis.
[0018] With such a microscope equipped with a solid immersion lens
moving device, the solid immersion lens is moved between an
inserted position, which contains the optical axis from the sample
to the objective lens, and a standby position, which is located
away from the optical axis, by the solid immersion lens moving
device. Both an observation image, which is taken in the normal
state in which the solid immersion lens is not set between the
sample and the objective lens, and a magnified observation image,
which is taken in the state in which the solid immersion lens is
inserted, can thus be acquired. By thus using the solid immersion
lens moving device, an observation image and a magnified
observation image can be acquired readily when both images are
required and observation of higher resolution is enabled by means
of the magnified observation image.
[0019] With this invention, "internal information" shall, for
example in cases where electronic devices are to be the samples,
include the circuit patterns of electronic devices as well as
emission of weak light from electronic devices. Such weak light
emissions include those caused by an abnormal position due to a
defect of an electronic device, transient light emission that
accompanies the switching operation of a transistor inside an
electronic device, etc. The generation of heat due to a defect of
an electronic device is also included.
[0020] Also, the microscope may have an arrangement equipped with
an image acquisition means for acquiring images of a sample that is
to be the observed object. In this case, the optical system is
arranged to guide a sample image to the image acquisition
means.
[0021] The above-described microscope can be used favorably as an
electronic device inspection device. In this case, the electronic
device inspection device is that which acquires an image of an
electronic device for inspection of internal information on the
electronic device, and this electronic device inspection device
preferably comprises: an image acquisition means, acquiring an
image of the electronic device that is to be the observed object;
an optical system, including an objective lens, onto which light
from the electronic device is made incident, and guiding the image
of the electronic device to the image acquisition means; and the
above-described solid immersion lens moving device; and preferably
the solid immersion lens moving device moves the solid immersion
lens between an inserted position, which contains an optical axis
from the electronic device to the objective lens; and a standby
position, which is located away from the optical axis.
[0022] With such an electronic device inspection device equipped
with a solid immersion lens moving device, the solid immersion lens
is moved between an inserted position, which contains the optical
axis from the electronic device to the objective lens and a standby
position, which is located away from the optical axis, by the solid
immersion lens moving device. Both an observation image, which is
taken in the normal state in which the solid immersion lens is not
set between the electronic device and the objective lens, and a
magnified observation image, which is taken in the state in which
the solid immersion lens is inserted, can thus be acquired. By thus
using the solid immersion lens moving device, an observation image
and a magnified observation image can be acquired readily when both
images are required and observation of higher resolution is enabled
by means of the magnified observation image.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] FIG. 1 is a block diagram showing an electronic device
inspection device equipped with a solid immersion lens moving
device of an embodiment of this invention.
[0024] FIG. 2 is a perspective view of a solid immersion lens
moving device and an objective lens as viewed from above.
[0025] FIG. 3 is a perspective view of the solid immersion lens
moving device and the objective lens as viewed from below.
[0026] FIG. 4 is a perspective view of a lower part of the solid
immersion lens moving device and the objective lens as viewed from
below from a different viewpoint from that of FIG. 3.
[0027] FIG. 5 is a bottom view of the solid immersion lens moving
device and the objective lens in the state wherein a solid
immersion lens is positioned at a standby position.
[0028] FIG. 6 is a bottom view of the solid immersion lens moving
device and the objective lens in the state wherein the solid
immersion lens is positioned at an inserted position or a closely
contacting position.
[0029] FIG. 7 is a bottom view of the solid immersion lens moving
device and the objective lens in the state wherein the solid
immersion lens is positioned at an exchange position.
[0030] FIG. 8 is a perspective view showing the solid immersion
lens holder.
[0031] FIG. 9 is a vertical section showing the solid immersion
lens holder in the state in which the lens is set at the standby
position.
[0032] FIG. 10 is a vertical section showing the solid immersion
lens holder in the state in which the lens is set at the closely
contacting position.
[0033] FIG. 11 is a perspective view showing a part at which an arm
part of the solid immersion lens holder and a first arm member of
the solid immersion lens moving device are connected.
[0034] FIG. 12 is a perspective view showing the state prior to
connection of the arm part of the solid immersion lens holder and
the first arm member of the solid immersion lens moving device as
viewed from the front.
[0035] FIG. 13 is a perspective view showing the state prior to
connection of the arm part of the solid immersion lens holder and
the first arm member of the solid immersion lens moving device as
viewed from the rear.
[0036] FIG. 14 is a block diagram showing the solid immersion lens
moving device and the objective lens along with an optical coupling
material supplying means and a drying gas supplying means.
[0037] FIG. 15 is a block diagram specifically showing the optical
coupling material supplying means.
[0038] FIG. 16 is a block diagram specifically showing the drying
gas supplying means.
[0039] FIG. 17 is a perspective view showing a solid immersion lens
holder used in another embodiment of this invention.
[0040] FIG. 18 is a vertical section showing the solid immersion
lens holder in the state in which a lens is set at the closely
contacting position.
[0041] FIG. 19 is a perspective view showing a part at which the
solid immersion lens holder is connected to a solid immersion lens
moving device.
[0042] FIG. 20 is a perspective view showing another solid
immersion lens holder.
[0043] FIG. 21 is a vertical section showing the other solid
immersion lens holder in the state wherein a lens is positioned at
a closely contacting position.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0044] Preferred embodiments of this invention's solid immersion
lens moving device and microscope shall now be described with
reference to FIG. 1 to FIG. 21. FIG. 1 is a block diagram showing
an electronic device inspection device equipped with a solid
immersion lens moving device of a first embodiment of this
invention, FIG. 2 to FIG. 4 are respectively perspective views
showing a solid immersion lens moving device and an objective lens,
FIG. 5 to FIG. 7 are respectively diagrams of states illustrating
moving operations of the solid immersion lens moving device, FIG. 8
to FIG. 10 are respectively diagrams showing the solid immersion
lens holder, FIG. 11 to FIG. 13 are respectively perspective views
showing a part at which the solid immersion lens holder and the
solid immersion lens moving device are connected, FIG. 14 to FIG.
16 are respectively diagrams showing an optical coupling material
supplying means and a drying gas supplying means, FIG. 17 to FIG.
19 are respectively diagrams showing a solid immersion lens holder
used in another embodiment of this invention, and FIGS. 20 and 21
are respectively diagrams showing another solid immersion lens
holder. In the respective figures, the same elements shall be
provided with the same symbols and redundant description shall be
omitted. This invention's solid immersion lens moving device and
microscope are generally applicable to sample observation using a
solid immersion lens. However, in the following description,
examples of application to electronic device inspection
(semiconductor inspection) shall mainly be described.
[0045] First, the electronic device inspection device equipped with
the solid immersion lens moving device of the first embodiment
shall be described. As shown in FIG. 1, electronic device
inspection device 1 is an inspection device, for which the object
of observation is a semiconductor device S, wherein a circuit
pattern, for example, of transistors and wiring, etc., is formed on
a semiconductor substrate, and images of this semiconductor device
S are acquired for inspection of the internal information thereof.
With this invention, "internal information" shall include circuit
patterns of semiconductor devices as well as emission of weak light
from semiconductor devices. Such weak light emissions include those
caused by an abnormal position due to a defect of a semiconductor
device, transient light emission that accompanies the switching
operation of a transistor inside a semiconductor device, etc. The
generation of heat due to a defect of a semiconductor device is
also included.
[0046] This electronic device inspection device 1 is equipped with
an observation part A for performing observation of semiconductor
device S, a control part B for controlling the operations of the
respective parts of observation part A, and an analysis part C for
performing the processing, instructing, etc., necessary for the
inspection of semiconductor device S. Semiconductor device S is
set, with its rear surface facing upward, on a stage 18, provided
in observation part A, and in the present embodiment, inspection
device 1 is used to inspect the lower surface in the figure of
semiconductor device S (integrated circuits, etc., formed on a
semiconductor substrate surface of semiconductor device S).
[0047] Observation part A is equipped with a high-sensitivity
camera 10 and a laser scanning microscope (LSM) unit 12, which are
image acquisition means for acquiring images from semiconductor
device S, an optical system 2, which includes an objective lens 20
of a microscope 4 that is positioned between semiconductor device S
and high-sensitivity camera 10 and LSM unit 12, a solid immersion
lens 3, for obtaining magnified observation images of semiconductor
device S, a solid immersion lens manipulator 30, which is a solid
immersion lens moving device that moves solid immersion lens 3 in
three-dimensional directions, and an X-Y-Z stage 15, which moves
the above-mentioned components respectively in orthogonal X, Y, and
Z directions.
[0048] In addition to the abovementioned objective lens 20, optical
system 2 is equipped with a camera optical system 22 and an LSM
unit optical system 24. A plurality of objective lenses 20 of
different magnifications are provided in a switchable manner.
Camera optical system 22 guides light from semiconductor device S
that has passed through an objective lens 20 to high-sensitivity
camera 10, and high-sensitivity camera 10 thereby acquires an image
of a circuit pattern, etc., of semiconductor device S. Meanwhile,
LSM unit optical system 24 guides infrared laser light from LSM
unit 12 to semiconductor device S by reflecting the light to the
objective lens 20 side by means of a beam splitter (not shown) and
branches, by means of the beam splitter, a part of reflected light
from semiconductor device S that is directed towards
high-sensitivity camera 10 via objective lens 20 and guides this
light to LSM unit 12.
[0049] This LSM unit 12 scans an infrared laser light in the X-Y
directions and emits this light towards the semiconductor device S
side and detects the reflected light from semiconductor device S by
means of a photodetector (not shown). The intensity of this
detected light will be an intensity that reflects the circuit
pattern of semiconductor device S. Thus by X-Y scanning of
semiconductor device S by infrared laser light, LSM unit 12
acquires an image of the circuit pattern, etc., of semiconductor
device S.
[0050] X-Y-Z stage 15 is for moving high-sensitivity camera 10, LSM
unit 12, optical system 2, solid immersion lens 3, solid immersion
lens manipulator 30, etc., as necessary in each of the X-Y
directions (horizontal directions; directions parallel to
semiconductor device S, which is the observed object) and the Z
direction (vertical direction) orthogonal to the X-Y
directions.
[0051] Solid immersion lens 3 is a microlens having a hemispherical
shape (see FIG. 9) or a hyperhemispherical shape, called a
Weierstrass sphere, of a size of approximately 1 mm to 5 mm. By the
bottom surface of this solid immersion lens 3 coming into close
contact with an observation position (the illustrated upper
surface) for observing semiconductor device S, a magnified
observation image of the surface (the illustrated lower surface) of
semiconductor device S at the rear side is obtained.
[0052] Specifically, a solid immersion lens that is used in a
semiconductor inspection device is formed of a high refractive
index material that is practically the same or close to the
substrate material of the semiconductor device in refractive index.
Representative examples of this material include Si, GaP, GaAs,
etc.
[0053] By putting such a microscopic optical element into close
optical contact with a substrate surface of a semiconductor device,
the semiconductor substrate itself can be put to use as a part of
the solid immersion lens. In rear surface analysis of a
semiconductor device using a solid immersion lens, in setting the
focal point of an objective lens to an integrated circuit formed on
a surface of a semiconductor substrate, the effect of the solid
immersion lens enables the focal point position to be set so as not
to be as deep as that in air. Light flux of high NA can thus be
made to pass through the substrate and the achievement of high
resolution by use of short wavelengths can be anticipated.
[0054] The lens shape of such a solid immersion lens 3 is
determined by conditions with which aberrations are eliminated.
With a solid immersion lens having a hemispherical shape, the
sphere center thereof becomes the focal point. In this case, both
the numerical aperture NA and the magnification are multiplied by
n. On the other hand, with a solid immersion lens with a
hyperhemispherical shape, the focal point is located at a position
shifted downward by R/n from the sphere center. In this case, both
the numerical aperture NA and the magnification are multiplied by
n.sup.2. Solid immersion lens 3 of conditions besides the above,
such as that with which the focal point is positioned between the
sphere center and the position shifted downward by R/n from the
sphere center, etc., may be used in accordance with the specific
observation conditions, etc., for semiconductor device S.
[0055] Solid immersion lens holder 5 (see FIG. 8 to FIG. 10) is for
favorably supporting solid immersion lens 3. Also, solid immersion
lens manipulator 30 (see FIG. 2 to FIG. 7), which moves this solid
immersion lens holder 5 in three-dimensional directions, is for
moving solid immersion lens 3, which is supported by solid
immersion lens holder 5, to the respective predetermined positions
of: an inserted position, which is a position between semiconductor
device S and objective lens 20 and includes an optical axis from
semiconductor device S to objective lens 20; a closely contacting
position, at which the bottom surface of solid immersion lens 3 is
put in close contact with an observation position of semiconductor
device S; a standby position, which lies outside the
above-mentioned optical axis; an exchange position for exchanging
solid immersion lens 3, etc. This solid immersion lens holder 5 and
solid immersion lens manipulator 30 shall described in detail
later.
[0056] Control part B is equipped with a camera controller 51a, a
laser scan (LSM) controller 51b, a stage controller 52, and a
manipulator controller 53. Camera controller 51a and LSM controller
51b control the operations of high-sensitivity camera 10 and LSM
unit 12, respectively, and thereby control the execution of the
observation of (acquisition of images from) semiconductor device S,
which is carried out in observation part A, as well as the setting
of the observation conditions, etc.
[0057] Stage controller 52 controls the operation of X-Y-Z stage 15
and thereby controls the movement, positioning, focusing, etc., of
high sensitivity camera 10, LSM unit 12, optical system 2, etc., to
positions corresponding to the observation position of
semiconductor device S. Manipulator controller 53 controls the
operation of solid immersion lens manipulator 30 and thereby
controls movements of solid immersion lens 3 to the abovementioned
predetermined positions as well as fine adjustment of the closely
contacting position of solid immersion lens 3, etc. (details shall
be provided later).
[0058] Analysis part C is equipped with an image analysis part 61
and an instructing part 62 and is arranged from a computer. Image
analysis part 61 performs the necessary analysis processes, etc.,
on image information from camera controller 51a and laser scan
controller 51b. Instructing part 62 references the contents input
by an operator, the contents of analysis by image analysis part 61,
etc., and provides the necessary instructions concerning the
execution of inspection of semiconductor device S in observation
part A, via the control part B. The image, data, etc., that have
been acquired or analyzed at analysis part C are displayed as
necessary on a display device 63, connected to analysis part C.
[0059] Solid immersion lens holder 5 and solid immersion lens
manipulator 30, which make up the characteristics of the present
embodiment, shall now be described in detail.
[0060] As shown in FIG. 8 and FIG. 9, solid immersion lens holder 5
is equipped with a holder 6, which is formed to a substantially
cylindrical form and supports solid immersion lens 3, and an arm
part 7, which holds this holder 6. Since this solid immersion lens
holder 5 comes in contact with an optical contact liquid to be
described below in some cases, it is formed, for example, of
stainless steel, aluminum, or other metal of high corrosion
resistance or of a resin, such as acrylic resin, PET, polyethylene,
polycarbonate, etc., which can be formed readily in accordance with
the shape of the solid immersion lens.
[0061] As shown in FIG. 9, holder 6 is equipped with a first holder
8, which holds solid immersion lens 3, and a second holder 9, which
supports this first holder 8. This first holder 8 and second holder
9 are formed to a substantially cylindrical form so as not to
obstruct the optical path with respect to semiconductor device
S.
[0062] First holder 8 is equipped on the outer peripheral surface
of an upper part thereof with an annular collar part 8a, which
protrudes outwards, and is equipped on the bottom surface with an
annular collar part 8b, which is directed inwards, and solid
immersion lens 3 is held by being fixed, for example, by an
adhesive agent, etc., to first holder 8 in a state in which the
bottom surface of solid immersion lens 3 protrudes downward through
an opening formed at the inner periphery of annular collar part
8b.
[0063] Second holder 9 is equipped at its bottom surface with an
inwardly directed annular collar part 9a. Annular collar part 8a of
first holder 8 is set on annular collar part 9a of second holder 9
and first holder 8 and solid immersion lens 3 are supported in the
gravity direction by second holder 9 in a state wherein a lower
part of first holder 8 is protruded downward through an opening 9b,
formed at the inner periphery of annular collar part 9a.
[0064] Here, if the outer diameter of the lower part of first
holder 8 is A, the outer diameter of annular collar part 8a of
first holder 8 is B, and the inner diameter of opening 9b of second
holder 9 is C, these are set to satisfy the relationship,
A<C<B. First holder 8 is made free with respect to second
holder 9 and yet the falling-off of first holder 8 downwards from
second holder 9 is prevented.
[0065] Second holder 9 is also equipped at an opening 9c at an
upper part thereof with a cap 11, which is mounted by fitting,
screwing, etc., and is for preventing the falling off of the solid
immersion lens. As with first holder 8 and second holder 9, this
cap 11 is formed to a substantially cylindrical form, and if the
inner diameter of cap 11 is D, it is set to satisfy the
relationship, D<B. Thus by means of cap 11, separation, such as
the springing out of first holder 8, which holds solid immersion
lens 3, through opening 9c at the upper part of second holder 9, is
thus prevented and the loss of the solid immersion lens is
prevented without obstruction of the optical path for semiconductor
device S.
[0066] Also, arm part 7 is arranged by bending a round bar to a
substantially L-like shape and extends outward from second holder 9
with one end thereof being directed upwards and the other end
thereof being fixed to a side part of second holder 9. As shown in
FIG. 8 and FIG. 9, a rotation stopping part 7a, with which a part
of a side face of a pipe is made a flat surface, is fixed, for
example, by fitting, etc., onto one end of arm part 7 as a rotation
stop for arm part 7 and holder 6. Though arm part 7 is arranged to
be substantially L-like in shape and has one end thereof extending
upward, it may be arranged to extend within the X-Y plane
instead.
[0067] As shown in FIG. 11, arm part 7, which makes up this solid
immersion lens holder 5, is detachably connected to one end of a
first arm member 71 of solid immersion lens manipulator 30. As
shown in FIG. 12 and FIG. 13, connecting part 99, which connects
this first arm member 71 with solid immersion lens holder 5, is
equipped at first arm member 71 with a through hole 71a, through
which rotation stopping part 7a of arm part 7 can be inserted in
the vertical direction, and a fastening part 71b, which has its
front end face formed to a flat surface and which narrows or
spreads through hole 71a by being screwed forward or backward
(advancing or retreating).
[0068] In this arrangement, rotation stopping part 7a, which has
been inserted in through hole 71a, is fixed to first arm member 71
by advancing fastening part 71b by turning it in the fastening
direction. In this state, the flat surface of rotation stopping
part 7a of arm part 7 is made to contact and then put in close
contact with the flat surface at the front end of fastening part
71b, thereby arranging a rotation stop for arm part 7 and solid
immersion lens holder 5. Also, arm part 7, which has thus been
fixed to first arm member 71, can be released and extracted from
first arm member 71, for example, for exchange of solid immersion
lens 3, etc., by retreating fastening part 71b by rotating it in
the opposite direction.
[0069] Solid immersion lens manipulator 30, which holds solid
immersion holder 5 by means of this connecting part 99, freely
moves solid immersion lens 3 in solid immersion lens holder 5 to
the respective abovementioned predetermined positions (inserted
position, closely contacting position, standby position, and
exchange position) in three-dimensional directions as shown in FIG.
1 to FIG. 7. As shown in FIG. 2 to FIG. 7, this solid immersion
lens manipulator 30 is equipped with the above-described first arm
member 71, to which solid immersion lens holder 5 is mounted, a
first arm member rotation source 72, which rotates this first arm
member 71 within the X-Y plane, a second arm member 73, which holds
this first arm member rotation source 72, a second arm member
rotation source 74, which rotates this second arm member 73 within
the X-Y plane, and a Z-direction movement source 75, which moves
this second arm member rotation source 74 in the Z-direction that
is orthogonal to the X-Y plane, and this Z-direction movement
source 75 is deemed to be at the base end side and the moving first
arm member 71 is deemed to be the terminal end side.
[0070] Specifically, Z-direction movement source 75 is arranged
from a Z-axis motor, etc., with which a movement shaft 75a is moved
in the Z-direction, for example, by a feeding screw, etc., and is
mounted to microscope 4 as the main device body side via a
supporting part 76. This supporting part 76 is detachably mounted
to microscope 4, for example, by being screwed on, etc., so as to
be convenient, for example, for carrying out microscopic
observation upon removing solid immersion lens manipulator 30 or
carrying out microscopic observation upon mounting another lens
moving device.
[0071] Second arm member rotation source 74 is connected via a
supporting part 77 to movement shaft 75a of Z-direction movement
source 75. This second arm member rotation source 74 is arranged
from a motor, etc., with which the output shaft is, for example, a
rotation axis 74a, which rotates in the forward and reverse
directions (needs only to rotate within a predetermined range), and
is moved in the Z-direction by the driving of Z-direction movement
source 75.
[0072] One end of second arm member 73 is connected to this
rotation axis 74a of second arm member rotation source 74. Though
details shall be given later, this second arm member 73 is arranged
in a curving manner so that second arm member 73 can be moved away
readily from the field of view of the observation position of
semiconductor device S (field of view of objective lens 20) as
shown in FIG. 6.
[0073] First arm member rotation source 72 is fixed to the other
end of second arm member 73 as shown in FIG. 2 to FIG. 7. This
first arm member rotation source 72 is arranged from a motor, etc.,
with which the output shaft is, for example, a rotation axis 72a,
which rotates in the forward and reverse directions (needs only to
rotate within a predetermined range). Rotation axis 72a of first
arm member rotation source 72 and rotation axis 74a of second arm
member rotation source 74 are thus positioned non-coaxially. By the
driving of second arm member rotation source 74, first member
rotation source 72 is rotated along with second arm member 73
within the X-Y plane and with rotation axis 74a of second arm
member rotation source 74 as the supporting point.
[0074] The other end of the above-described first arm member 71 is
connected to rotation axis 72a of first arm member rotation source
72. This first arm member 71 is rotated within the X-Y plane and
with rotation axis 72a of first arm member rotation source 72 as
the supporting point by the driving of first arm member rotation
source 72.
[0075] Thus by the driving of first arm member rotation source 72
and second arm member rotation source 74, solid immersion lens 3,
supported by solid immersion lens holder 5 connected to one end of
first arm member 71, is moved in synthetic directions, resulting
from the synthesis of the respective rotations, within the X-Y
plane, is also moved in the Z-direction by the driving of
Z-direction movement source 75, and is consequently moved freely to
the respective predetermined positions in three-dimensional
directions.
[0076] Furthermore, solid immersion lens manipulator 30 of this
embodiment is used for obtaining a magnified observation image by
means of solid immersion lens 3, and, as shown in FIG. 14, is
equipped with an optical coupling material supplying means 80,
which supplies an optical coupling material for optically coupling
solid immersion lens 3 to the observation position of semiconductor
device S, and a drying gas supplying means 90, which supplies a gas
for drying this optical coupling material.
[0077] Optical coupling material supplying means 80 supplies an
optical contact liquid (comprising, for example, water and a
surfactant), which contains, for example, amphiphilic molecules, to
the observation position of semiconductor device S immediately
prior to bringing solid immersion lens 3 into close contact with
the observation position. With this optical coupling material
supplying means 80, an optical contact liquid is contained inside a
compact dedicated liquid tank 81, which has a volume, for example,
of lcc and is fixed to supporting part 76 as shown in FIG. 14 and
FIG. 15. The contained optical contact liquid is then put in a
pressurized state by means of a compressed gas, such as compressed
air, etc., and by supplying a pulse signal from a control system 83
to a microvalve 82, which, for example, is a solenoid valve that is
equipped with a spring, is fixed to supporting part 76, and is
connected to the exit of liquid tank 81, the optical contact liquid
is sprayed from a supply port 85a at the tip of an optical coupling
material supply pipe 85, which is connected to microvalve 82 via a
flexible pipe 84 and is fixed to first arm member 71 as shown in
FIG. 2 to FIG. 7.
[0078] It is sufficient that the amphiphilic molecule be a molecule
having both a hydrophilic group (carboxyl group, sulfo group,
quaternary ammonium group, hydroxyl group, etc.) and a hydrophobic
group (also called a lipophilic group; examples include long-chain
hydrocarbon groups, etc.), and, for example, a surfactant molecule
(ionic surfactant molecule or nonionic surfactant molecule) may be
used favorably. Other examples of amphiphilic molecules include
glycerin, propylene glycol, sorbital, and other wetting agents,
phospholipids, glycolipids, aminolipids, etc.
[0079] Since the optical contact liquid, which contains amphiphilic
molecules, is low in surface tension, it spreads across the
semiconductor substrate, which is a hydrophobic surface. In the
process of drying this optical contact liquid, forces that tend to
maintain the wettability of the surface of the semiconductor
substrate and the bottom surface of the solid immersion lens become
dominant. The vaporization of mainly the water of the optical
contact liquid thus progresses while the surface interval between
the bottom surface of the solid immersion lens and the
semiconductor substrate surface narrows. In the final stage, the
solid immersion lens and the semiconductor substrate become
optically coupled.
[0080] It is considered that in this state, van der Waals forces
act between water molecules and the hydrophilic groups of the
amphiphilic molecules, which have become physically adsorbed onto
the semiconductor substrate surface and the bottom surface of the
solid immersion lens, and due to the binding of water molecules,
the vaporization thereof is stopped. The distance between the solid
immersion lens and the semiconductor substrate at this point can be
made, for example, no more than 1/20.lambda. (.lambda.:
illumination wavelength), and as a result, evanescent coupling as
well as physical fixation of the solid immersion lens and the
semiconductor substrate are achieved. "Optical contact" in this
invention shall refer to a state wherein optical coupling is
achieved by evanescent coupling.
[0081] As an optical coupling material besides the above-described
optical contact liquid, a refractive index matching fluid (index
matching liquid, etc.), such as that described in Japanese Patent
Publication No. H7-18806 and with which refractive index matching
of a solid immersion lens and a semiconductor substrate is
achieved, can be cited. A refractive index matching fluid differs
from an optical contact liquid, and whereas the former realizes a
high NA by means of the refractive index of a fluid, the latter has
a role of aiding evanescent coupling. Though an embodiment using an
optical contact liquid shall be described in detail here, the same
effects can be realized with an embodiment using a refractive index
matching fluid. However in such a case, since the fluid does not
have to be dried necessarily, an embodiment is possible wherein
drying gas supplying means 90 is omitted.
[0082] This optical coupling material supply pipe 85 is fixed to
first arm member 71 and supply port 85a at the front end thereof is
set near solid immersion lens holder 5 as shown in FIG. 2 to FIG.
7. The pipe thus moves along with solid immersion lens 3 and is
enabled to spray the optical contact liquid towards the targeted
observation position. This optical contact liquid is controlled in
sprayed amount by control of the duration during which the pulse
signal is on and is sprayed from supply port 85a at a precision of
the picoliter level. The sprayed amount of optical contact liquid
is determined suitably in accordance with the size of solid
immersion lens 3. Also, this optical contact liquid is preferably
exchanged as suited in order to prevent decomposition, change of
concentration, and clogging by the liquid.
[0083] In place of microvalve 82, an optical coupling material
supplying means may be used wherein a tubing type microdispenser is
used and, without pressurizing liquid tank 81 by compressed gas,
the tube of the tubing type microdispenser is mechanically squeezed
to make the optical contact liquid inside liquid tank 81 drip
towards the observation position from supply port 85a at the front
end of optical coupling material supply pipe 85 via flexible pipe
84. In this case, the capacity of liquid tank 81 is set to a few
dozen cc's and the dripping amount is determined as suited
according to the size of solid immersion lens 3.
[0084] Drying gas supplying means 90 supplies a gas for rapidly
drying the optical contact liquid between the observation position
of semiconductor device S and solid immersion lens 3. As shown in
FIG. 14 and FIG. 16, with this drying gas supplying means 90,
ON/OFF signals are supplied from a control system 93 to a solenoid
valve 92, fixed to support part 76, to make a gas, such as
compressed dried air, nitrogen gas, etc., be blown out from a
supply port 95a at the tip of a gas supply pipe 95, which is
connected to solenoid valve 92 via a flexible pipe 94 and is fixed
to first arm member 71 as shown in FIG. 2 to FIG. 7.
[0085] As with optical coupling material supply pipe 85, this gas
supply pipe 95 is fixed to first arm member 71 and supply port 95a
at the front end thereof is set near solid immersion lens holder 5
as shown in FIG. 2 to FIG. 7. The pipe thus moves along with solid
immersion lens 3 and is enabled to blow gas towards the targeted
position between the observation position of the semiconductor
device and solid immersion lens 3.
[0086] The actions of electronic device inspection device 1, having
the above-described arrangement, shall now be described. The
description shall start from the state, shown in FIG. 5, wherein
solid immersion lens 3 is positioned at the standby position. At
this standby position, first and second arm members 71 and 73 are
folded and solid immersion lens 3 and first and second arm members
71 and 73 are set outside the view field of objective lens 20. At
this point, first holder 8, holding solid immersion lens 3, has its
annular collar part 8a set on annular collar part 9a of second
holder 9 and first holder 8 and solid immersion lens 3 are
supported in the gravity direction by second holder 9 as shown in
FIG. 9. In this standby state, a pattern image, which is a normal
observation image of the observation position of semiconductor
device S is acquired and then, for example, a voltage is applied,
etc., to semiconductor device S and the image in this process is
acquired.
[0087] Here, if there is an abnormal position in semiconductor
device S, an emission image will be obtained, and the abnormal
position of semiconductor device S can thus be specified by
overlapping the normal observation image with the image obtained
when a voltage was applied. In the case where there is an abnormal
position, high-sensitivity camera 10, LSM unit 12, optical system
2, solid immersion lens holder 5, solid immersion lens manipulator
30 are moved by means of X-Y-Z stage 15 so that objective lens 20
will be positioned coaxial to the abnormal position.
[0088] Solid immersion lens 3 is then set with respect to the
observation position of semiconductor device S. In this case,
firstly, first and second arm member rotation sources 72 and 74 of
solid immersion lens manipulator 30 are driven and by thus rotating
first and second arm members 71 and 73, solid immersion lens 3, at
the standby position, is moved to the inserted position, between
semiconductor device S and objective lens 20 and containing the
optical axis from semiconductor device S to objective lens 20 as
shown in FIG. 3, FIG. 4 and FIG. 6. Here, since second arm member
73 is formed to have a curved shape, second arm member 73 is kept
readily away from the view field without obstructing the view field
of objective lens 20 as shown in FIG. 6.
[0089] When solid immersion lens 3 has thus been inserted at the
inserted position, Z-direction movement source 75 of solid
immersion lens manipulator 30 is driven to lower solid immersion
lens 3. When solid immersion lens 3 then approaches the observation
position, optical contact liquid is supplied to the observation
position, which is the targeted position, from optical coupling
material supplying means 80 and solid immersion lens 3 is set on
the observation position and positioned at the closely contacting
position.
[0090] When solid immersion lens 3 is thus set on the observation
position of semiconductor device S, solid immersion lens 3 and
first holder 8, which are supported in the gravity direction by
second holder 9, are raised by semiconductor device S as shown in
FIG. 10.
[0091] Fine adjustment of the closely contacting position of solid
immersion lens 3 is then carried out. This fine adjustment is
carried out by minutely moving solid immersion lens holder 5 in the
Z-direction by the driving of Z-direction movement source 75 of
solid immersion lens manipulator 30 and minutely swinging first arm
member 71 by means of first arm member rotation source 72 and these
are carried out so that first holder 8, holding solid immersion
lens 3, will be spaced apart in the X-Y-Z directions from second
holder 9 and thus will not contact second holder 9. Specifically,
an image containing reflected light from solid immersion lens 3 is
acquired, and the reflected light from the reflecting surfaces of
various parts of solid immersion lens 3 in the reflected light
image, contained in the abovementioned image, are used as
guides.
[0092] More specifically, analysis is performed automatically or
based on instructions from an operator on the acquired image by
means of image analysis part 61 of analysis part C to determine the
position of the center of gravity of the reflected light image.
Then by means of instructing part 62 of analysis part C, solid
immersion lens manipulator 30 is instructed via manipulator
controller 53 to perform fine adjustment of the closely contacting
position of solid immersion lens 3 so that the center of gravity
position of the reflected light image obtained at image analysis
part 61 matches the observation position at semiconductor device S.
The positioning of solid immersion lens 3 with respect to the
observation position of semiconductor device S and objective lens
20 is thus carried out.
[0093] Since solid immersion lens 3 and first holder 8 are put in a
free state with respect to second holder 9 in a state in which
these are raised by semiconductor device S, only the weights of
solid immersion lens 3 and first holder 8 themselves act on the
observation position of semiconductor device S and thus the
application of an excessive force is eliminated and yet solid
immersion lens 3 is put in close contact in conformance
(compliance) to the observation position.
[0094] Gas is then supplied by means of drying gas supplying means
90 to the region at which solid immersion lens 3 contacts the
observation position, which is the targeted position, and by thus
drying the optical contact liquid, solid immersion lens 3 is
rapidly put into definite, close contact with the observation
position of semiconductor device S. Since solid immersion lens 3 is
thus put into definite, close contact with the observation position
of semiconductor device S by means of the optical contact liquid
from optical coupling material supplying means 80, high-precision
observation is enabled, and since the drying of the optical contact
liquid is promoted by the gas from drying gas supplying means 90,
immediate execution of observation is enabled.
[0095] When close contact of solid immersion lens 3 with the
observation position is thus achieved, adjustment of the distance,
between semiconductor device S, on and with which solid immersion
lens 3 is set and put in close contact, and objective lens 20, is
instructed from instructing part 62 to X-Y-Z stage 15 via stage
controller 52 to perform focusing. In this process, since solid
immersion lens manipulator 30 and solid immersion lens 3 move in
the Z-direction along with objective lens 20, solid immersion lens
3 is made to move in the opposite Z-direction by means of solid
immersion lens manipulator 30 so as to maintain the close contact
of solid immersion lens 3 with the observation position. A
magnified observation image of the observation position is then
acquired via optical system 2, which includes objective lens 20 and
solid immersion lens 3 that is put in close contact with the
observation position of semiconductor device S, and high resolution
observation is carried out.
[0096] During this observation, since solid immersion lens 3 and
first holder 8 are put in a free state with respect to second
holder 9 as described above, temperature drifts at the second
holder 9 side or the semiconductor device S side are cut off with
respect to the counterpart side and the influences of these
temperature drifts are thus eliminated.
[0097] For observation of the next observation position, the
optical contact liquid is supplied again from optical coupling
material supplying means 80, the close contact of solid immersion
lens 3 with the observation position is thereby released, and
thereafter, solid immersion lens holder 5 is moved by solid
immersion lens manipulator 30 by the reverse procedures as the
procedures described above to move solid immersion lens 3 to the
standby position shown in FIG. 5. Subsequently, the same procedures
as those described above are repeated.
[0098] In place of the optical contact liquid, the solvent thereof
may be used to release the optical contact. The optical contact is
released by wetting the contacting portion with the optical contact
liquid or the solvent thereof since the optical contact liquid or
solvent thereof reenters into the boundary surface between the
solid immersion lens and the semiconductor substrate and destroys
the optically coupled state and the physically fixed state. By this
method, the solid immersion lens and the semiconductor device can
be separated without applying an excessive force. Since the
semiconductor device and the solid immersion will thus not become
flawed, the solid immersion lens can be reused.
[0099] Here, if the need to exchange solid immersion lens 3 arises,
first arm member rotation source 72 of solid immersion lens
manipulator 30 is driven to rotate first arm member 71 to move
solid immersion lens 3 from the standby position shown in FIG. 5,
at which connecting part 99 is positioned close to a lower part of
second arm member 73 and is difficult to handle, to the lens
exchange position shown in FIG. 2 and FIG. 7. Connecting part 99 is
moved outward greatly from near the lower part of second arm member
73 and solid immersion lens holder 5 is exchanged together with arm
part 7. Since connecting part 99 is set at a handling position in
the process of lens exchange, the detachment and attachment of arm
part 7 of solid immersion lens holder 5 with respect to first arm
member 71 is facilitated, and since solid immersion lens holder 5
is exchanged along with arm part 7, the minute solid immersion lens
3 does not have to be handled and the exchange of the lens is thus
facilitated.
[0100] Thus with solid immersion lens holder 5 of the present
embodiment, only the weights of solid immersion lens 3 and first
holder 8 themselves act on the observation position of
semiconductor device S and the application of an excessive pressure
is thus eliminated. Damaging of semiconductor device S can thus be
prevented. Also, solid immersion lens 3 is put in close contact in
conformance (compliance) with the observation position and yet
temperature drifts at the second holder 9 side or the semiconductor
device S side are cut off from the counterpart side and thus the
influences of such temperature drifts are eliminated.
High-precision observation is thus enabled without peeling off of
solid immersion lens 3 from the observation position.
[0101] Also, with solid immersion lens manipulator 30 of the
present embodiment, solid immersion lens 3 is moved to
predetermined positions within the X-Y plane by rotation of first
and second arm members 71 and 73. There is thus no need to make the
component parts long in the orthogonal X and Y directions, and a
simple arrangement that occupies a small area is provided.
Compactness of device can thus be realized while realizing low
cost.
[0102] Also, with electronic device inspection device 1, equipped
with this solid immersion lens manipulator 30, when both an
observation image, which is taken in the normal state in which
solid immersion lens 3 is not set between semiconductor device S
and objective lens 20, and a magnified observation image, which is
taken in the state in which solid immersion lens 3 is inserted, are
to be acquired, these images can be acquired readily. Also, in this
case, since high resolution observation is carried out by the
magnified observation image, inspection using electronic device
inspection device 1 can be carried out readily and with high
precision.
[0103] FIG. 17 is a perspective view showing a solid immersion lens
holder used in another embodiment of this invention, and FIG. 18 is
a vertical section showing the solid immersion lens holder in the
state in which a lens is set at a closely contacting position.
Also, FIG. 19 is a perspective view showing a part at which the
solid immersion lens holder and a solid immersion lens moving
device are connected. As shown in FIG. 17 and FIG. 18, solid
immersion lens holder 105 is equipped with a holder 106 formed to a
substantially cylindrical form, which supports solid immersion lens
103, and an arm part 107, which holds this holder 106.
[0104] As shown in FIG. 18, holder 106 is equipped with a lower
holder 108 and an upper holder 109. Of these, upper holder 109 is
arranged as an annular part that is formed integral to arm part
107. Lower holder 108, for supporting solid immersion lens 103, is
supported by arm part 107 via this upper holder 109. These holders
108 and 109 are formed to substantially cylindrical forms so as not
to obstruct the optical path with respect to semiconductor device
S.
[0105] Solid immersion lens 103 is arranged to have a shape wherein
a central part 103a of the bottom surface thereof protrudes
downward with respect to a peripheral part 103b thereof. With the
present embodiment, the outer peripheral surface of the protruding
central part 103a has a tapered shape that decreases in outer
diameter towards the lower side.
[0106] Holder 108 is formed to a substantially cylindrical form and
is equipped with an annular collar part 108a, which is directed
inwards, at the bottom surface thereof. Peripheral part 103b of
solid immersion lens 103 is set on annular collar part 108a of
holder 108 in the state in which the bottom surface of the
protruding central part 103a of solid immersion lens 103 protrudes
downward from an opening 108b formed in the inner periphery of
annular collar part 108a, and solid immersion lens 103 is thereby
supported in the gravity direction by holder 108.
[0107] Also, a cap 111 is provided above holders 108 and 109. By
this cap 111, the falling-off of solid immersion lens 103 from
holders 108 and 109 is prevented without obstruction of the optical
path with respect to semiconductor device S. Cap 111 of the present
embodiment has an annular form and has an arrangement having a
plurality of claw parts (three claw parts in the figure) that
protrude towards the inner side.
[0108] Also, arm part 107 is formed of a plate-like member that
extends outward from upper holder 109, with one end thereof being
directed obliquely upward and the other end thereof being
integrated with upper holder 109 as mentioned above. As shown in
FIG. 17 and FIG. 18, a rotation stopping part 107a, which extends
vertically upwards and with which a part of its side face is made a
flat surface, is fixed to the one end of arm part 107 as a rotation
stop for arm part 107 and holder 106.
[0109] As shown in FIG. 19, arm part 107, which makes up solid
immersion lens holder 105, is connected to one end of first arm
member 71 of solid immersion lens manipulator 30. Furthermore with
the present embodiment, first arm member 71 of solid immersion lens
manipulator 30 is arranged to be detachably attachable to first arm
member rotation source 72. In the arrangement example shown in FIG.
19, first arm member 71 is detachably connected to rotation axis
72a of first arm member rotation source 72 by means of a hexagon
socket head bolt 72b.
[0110] With such a solid immersion lens holder 105, though
processing is required of solid immersion lens 103, since only the
self-weight of solid immersion lens 103 acts on semiconductor
device S, the merit that it is even more unlikely for an excessive
pressure to be applied to semiconductor device S is provided.
[0111] Also, with the above-described embodiment, first arm member
71, to which solid immersion lens holder 105 is connected, is
arranged to be detachably mounted to first arm member rotation
source 72. By thus making first arm member rotation source 72, of
comparatively high rigidity, an attachable/detachable part, the
occurrence of deformation of first arm member 71 or arm part 107 of
solid immersion lens holder 105 is prevented and these members are
thus improved in durability. Also in performing observation of a
sample by means of solid immersion lens 103, the parallelism of the
observed object and solid immersion lens 103 can be maintained
favorably.
[0112] Also with an arrangement wherein first arm member 71 is
mounted to first arm member rotation source 72 by means of a bolt,
etc., as shown in FIG. 19, the attachment/detachment work can by
performed using a hexagonal wrench or other tool. The handling of
the device, for example, in exchanging solid immersion lens 103
along with first arm member 71 and solid immersion lens holder 105,
etc., is thus facilitated.
[0113] Also with the above-described embodiment, a part of holder
106 is arranged from upper holder 109, which is an annular part
that is integral to arm part 107. The rigidity of solid immersion
lens holder 105 can thereby be improved. Also, the positioning of
the arm part and the annular holder part of the solid immersion
lens holder (especially the positioning in the rotation direction)
is made unnecessary. With such an arrangement, the entirety of
holder 106 may be arranged from an annular part that is integral to
arm part 107.
[0114] Also, arm part 107 is made to have a shape that extends
obliquely upward from holder 106. Since space at the side of solid
immersion lens 103 can thus be secured, observation of a sample can
be carried out favorably. For example, in a case of inspecting a
plastic molded type IC, since steps are formed at the surroundings
of inspected positions due to mold cutting, the range in which the
solid immersion lens holder can be moved is restricted. However,
with the above arrangement wherein arm part 107 is made oblique,
interference between the steps of the observed object and the arm
part of the solid immersion lens holder can be lessened and
observation of the observed object using the solid immersion lens
can thus be carried out favorably.
[0115] With solid immersion lens holder 105 of the above-described
arrangement, lower holder 108, having annular collar part 108a, may
be made of the same or a similar material as that of upper holder
109 and arm part 107 or may be formed by processing a water
absorbing structure, such as a water absorbing ceramic. By applying
a water absorbing structure to the holder, the merit that, when an
excessive amount of optical contact liquid is applied, the time for
drying the liquid and bringing the solid immersion lens and the
observed object into close contact optically can be shortened is
provided.
[0116] FIG. 20 is a perspective view showing another solid
immersion lens holder and FIG. 21 is a vertical section showing
this other solid immersion lens holder in the state wherein a lens
is positioned at a closely contacting position. With this solid
immersion lens holder 64, holder 65, which makes up solid immersion
lens holder 64, is formed to have a cylindrical form and the inner
diameter thereof is made large in comparison to the outer diameter
of solid immersion lens 3. Solid immersion lens 3 is positioned in
the inner periphery of holder 65 with the bottom surface of this
solid immersion lens 3 protruding from an opening at the bottom
surface of holder 65.
[0117] With such a solid immersion lens holder 64, solid immersion
lens 3 is moved to a desired observation position by being moved in
a sliding manner across semiconductor device S while being hitched
onto the inner peripheral surface of holder 65 of solid immersion
lens holder 64, which moves within the X-Y plane. Solid immersion
lens holder 64 is then moved in the Z-direction and then solid
immersion lens holder 64 is furthermore moved within the X-Y plane,
thus leaving solid immersion lens 3 on the observation position of
semiconductor device S while solid immersion lens holder 64 is
moved away from solid immersion lens 3. The merit that observation
can be carried out upon moving all component parts away from the
view field of the observation position of semiconductor device S is
thereby provided.
[0118] Though the present invention has been described specifically
based on the embodiments above, this invention is not limited to
the above-described embodiments, and various modifications are
possible. For example, though with an above-described embodiment,
holder 9 for supporting solid immersion lens 3 is formed to have a
cylindrical form as an especially preferable form, this holder may
instead be a flat plate equipped with opening 9b.
[0119] Also with an above-described embodiment, solid immersion
lens manipulator 30 is enabled to move solid immersion lens 3 in
the Z-direction to thereby enable solid immersion lens 3 to be
moved freely to desired positions in three-dimensional directions
by a simple arrangement. However, Z-direction movement source 75
may be eliminated so that the lens manipulator is enabled to move
only within the X-Y plane and movement in the Z-direction may be
accomplished by means of X-Y-Z stage 15, or stage 18, on which
semiconductor device S is set, may be enabled to move in the
Z-direction. In such cases, the position at which solid immersion
lens 3 is inserted by solid immersion lens manipulator 30 is deemed
to be the closely contacting position.
[0120] Also, though with the above-described embodiments, a
semiconductor device, formed of a semiconductor substrate, is used
as an example of the observed object, this invention is not limited
thereto, and the observed object may be an electronic device with,
for example, a glass or plastic substrate. In this case, glass or
plastic is preferably used as the material of the solid immersion
lens.
[0121] Specifically, though with the above-described embodiments,
the observed sample is a semiconductor device, generally when
semiconductor devices and various other types of electronic devices
are used as samples, the device to be observed is not limited to
that which uses a semiconductor substrate, and the observed object
may be an integrated circuit, such as a polysilicon thin film
transistor that has glass or plastic, etc., as the substrate. For
example, with a liquid crystal device, the device is prepared on a
glass substrate, and with an organic EL, the device is prepared on
a plastic substrate. As even more general samples, biological
samples using prepared slides, etc., can be cited in addition to
the abovementioned semiconductor devices, liquid crystal devices,
and various other types of devices.
[0122] Also, though with each of the above-described embodiments,
application to inspection device 1 for semiconductor device S is
described as an especially effective application, this invention is
not limited thereto and may be applied, for example, to an optical
observation device, etc., for performing inspection of an optical
recording medium as an observed object, as described in Japanese
Patent Application Laid-Open No. H11-305135.
[0123] Also, the above-described solid immersion lens moving device
is generally applicable to a microscope for observing a sample and
obtaining internal information on the sample. In this case, the
microscope comprises an optical system, including an objective
lens, onto which light from a sample is made incident, and guiding
an image of the sample, and the solid immersion lens moving device,
and it is sufficient that the solid immersion lens moving device be
arranged to move the solid immersion lens between an inserted
position, which contains an optical axis from the sample to the
objective lens, and a standby position, which is located away from
the optical axis. Also, as mentioned above, the microscope may have
an arrangement equipped with an image acquisition means for
acquiring an image of the sample that is to be the observed object.
In this case, the optical system is arranged to guide the image of
the sample to the image acquisition means.
[0124] Also, though with each of the above-described embodiments, a
predetermined position of the lower surface of the observed object
(surface of semiconductor device S) is observed and solid immersion
lens 3 is used so that the focal point is set at a predetermined
position of the lower surface of the observed object, this
invention is not limited thereto, and in cases where the interior
or upper surface of an observed object is to be observed, a solid
immersion lens may be used to set the focal point in the interior
or at the upper surface of the observed object as described, for
example, in Japanese Patent Application Laid-Open No.
2001-189359.
[0125] As described above, with this invention's solid immersion
lens moving device, since the solid immersion lens is moved to
desired positions within the X-Y plane by the rotation of two arm
members, thus providing a simple arrangement that occupies a small
area with which there is no need to make the component parts long
in the orthogonal X and Y directions, compactness of the device can
be achieved while realizing low cost. Also with a microscope or an
electronic device inspection device equipped with this solid
immersion lens moving device, since in addition to providing the
effects of the solid immersion lens moving device, both an
observation image and a magnified observation image can be acquired
readily when both types of images are required and since
high-resolution observation is enabled by the magnified observation
image, electronic device inspection and other forms of sample
observation can be carried out readily and yet at high
precision.
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